India, Sept. 18 -- This is undeniably a new era for US audio giant Sonos. The company has rolled out Sonos 27, which you might think of as partly the operating system underpinning each Sonos audio product, but the scope is broader still. New additions are rolling out in stages between the Sonos app on your iPhone or Android phone and the Sonos speakers you have at home. This includes portable surrounds that become part of surround speaker system with a compatible soundbar such as the Arc Ultra, or a Sonos Ace Ultra headphones linking to move audio between themselves and compatible Sonos speakers depending on whether personal listening or room filling sound is prudent at any moment, as well as a Sonos 27voice assistant that evolves from So...